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Expired European patentEurope

Production of ultra-high purity oxygen by cryogenic air separation

EP 0446004 B1 · Applicant: AIR PRODUCTS AND CHEMICALS, INC.

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Overview

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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

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Why it's free to use

  • Filed March 4, 1991 and granted August 11, 1993. A European patent lasts at most 20 years from filing, so its term ended March 4, 2011.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by September 4, 2016.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledMarch 4, 1991
PublishedSeptember 11, 1991
GrantedAugust 11, 1993
Term endedMarch 4, 2011
Application numberEP 91301790
Classification (CPC)F25J3/0443 +2 more

Timeline

Timeline From EPO dates

1992199419961998200020022004200620082010Application filedMarch 4, 1991PublishedSep 11, 1991Patent grantedAug 11, 1993Term endedMarch 4, 2011

Sources & verification

Official EPO records

Full published documentClaims, description and drawings as a PDF.EPOEuropean Patent RegisterProcedure, status, file inspection and legal events.EPOLinked open EP data recordThe bibliographic record this page is built from.EPO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comEspacenetNational family members and their legal status.European Patent Office

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